1. Field of the Invention
The present invention relates to a labelling machine for labelling circular cylindrical containers or the like. Included is a rotary table having angularly controlled receiving positions for the containers positioned on the edge of the rotary table. A labelling station is located on the periphery of the rotary table and includes a labelling box for maintaining and dispensing a stack of labels. Each passing container removes a front label from the label box as it rolls by on a rotation controlled receiving position. A first adhesive unit is sensor controlled and applies adhesive to each container as the container moves by. There is also provided a second adhesive unit, which acts on the rear edge of the front label located in the label box.
2. Description of the Prior Art
Similar labelling machines are known. Primarily, they are used to perform so-called "all around labelling". Generally, with this type of labelling machine, the first adhesive unit sprays hot glue onto the container as soon as the sensor, which is attached to the adhesive unit., detects that there is a container within the effective area of the adhesive unit. The rotational movement of the receiving positions on the rotary table is arranged and controlled in such a manner that each container, with its adhesive area, meets the label front edge and, by means of adhesion of the adhesive, removes the front label from the label stack during its transport movement past the rotary table. The glue for the rear edge is applied by the second adhesive unit and is pressed into place by a stationary pressure element, during the transport of each container on the rotary table.
An accurate positioning of the labelling boxes and the adhesive units around the circumference of the rotary table is a very necessary prerequisite for trouble free labelling of the containers. This is normally done by taking into consideration the format of the containers to be labelled.
The quality of the labelling depends, to a considerable degree, on the accurate positioning of the labelling box. Since the container rolls past while removing the label, special attention must be paid to the adjustment of the label box. Inaccuracies can occur, even if large tolerances are acceptable within the same format. The faulty feeding of a label having a larger format can even cause damage to the labelling station.